成型方法对Si_(3)N_(4)-SiC耐火材料抗热震性能的影响  

Effects of preparation processes on thermal shock resistance of Si_(3)N_(4)-SiC refractories

作　　者：赵爽 李四超 杨自春[1] Zhao Shuang;Li Sichao;Yang Zichun(School of Power Engineering,Naval University of Engineering,Wuhan 430033,Hubei,China;不详)

机构地区：[1]海军工程大学动力工程学院,湖北武汉430033 [2]海军驻郑州地区军事代表室,河南郑州450015

出　　处：《耐火材料》2022年第5期386-390,共5页Refractories

基　　金：国家自然科学基金资助项目(51802347)。

摘　　要：为提高Si_(3)N_(4)-SiC材料的抗热震性,以工业级SiC颗粒和Si粉为原料,分别通过真空振动浇注成型和机压成型,再于1400℃保温8 h氮化烧结制备了Si_(3)N_(4)-SiC试样。测试其常规性能与密度分布,并设计水急冷法结合剩余断裂韧性的测试方案评价两种试样的抗热震性能。对比结果表明:真空振动浇注试样的常规性能优于传统机压试样的,并且断裂韧性保持率高于相同处理条件下的机压试样的,且试样密度分布均匀,减少了裂纹源区,能够有效提高试样的抗热震性。因此,真空振动浇注试样的抗热震性优于机压试样的。This work aims at improving the thermal shock resistance of Si_(3)N_(4)-SiC refractories.Si_(3)N_(4)-SiC specimens were prepared through two means:vacuum vibration casting and machine pressing,using industrial SiC particles and Si powder as raw materials and nitridation-firing at 1400℃ for 8 h.The properties and density distribution of the specimens were characterized,and a water quenching method combined with a residual fracture toughness test program was designed to evaluate the thermal shock resistance of the Si_(3)N_(4)-SiC refractories.The comparison results indicate that the vacuum vibration cast specimens have better general properties and higher fracture toughness retention ratio,more uniform density distribution and less crack sources than the traditional pressed specimens,hence the vacuum vibration cast specimens have better thermal shock resistance than the traditional pressed ones.

关 键 词：氮化硅结合碳化硅 抗热震性能 密度分布 断裂韧性 

分 类 号：TQ175.62[化学工程—硅酸盐工业]